1. Field of the Invention
The present invention relates to a small-sized opening and closing device well fitted especially to a foldable small-sized electronics device such as a portable telephone or a personal digital assistant, and so forth.
2. Description of the Related Art
Among small-sized electronics devices, as is a portable telephone, for example, there is a foldable type in which a transmitter section as a first member and a receiver section as a second member are constructed separately, and then relatively connected to open and close by means of a small-sized opening and closing device to which both members are attached to the connecting portion. Such a small-sized opening and closing device is publicly known as shown in Japanese Patent Laid-open No. 2000-337008.
The small-sized opening and closing device described in the above document has a structure that has a shaft which has an arresting portion on one end, a case body with a baffle, to which the shaft is inserted in the central axial direction and is arrested to the mentioned arresting portion, a slider cam which has a cam portion, which is slidably arrested in an axial direction to a key groove which is provided at an open end side of the mentioned case body, and is composed of a pair of a convex portion and a concave portion which is provided at a 180 degrees symmetric position on one end phase, and to which the mentioned shaft is inserted in the central axial direction, a cam member which has a cam portion composed of a pair of a concave portion and a convex portion which is provided at a 180 degrees symmetric position on an end section facing to the cam portion of the slider cam, and to which the mentioned shaft is inserted in the central axial direction, and a compression spring which is wound around the mentioned shaft, stored in the mentioned case body, and is interposed resiliently between this case body and the mentioned slider cam.